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  • THE EFFECTS OF ENRICHMENT ON COGNITION IN RATS (RATTUS NORVEGICUS)

    Author:
    Amber Alliger
    Year of Dissertation:
    2009
    Program:
    Psychology
    Advisor:
    Peter Moller
    Abstract:

    Abstract THE EFFECTS OF ENRICHMENT ON COGNITION IN RATS RATTUS NORVEGICUS by Amber A. Alliger Adviser: Dr. Peter Moller Animal models play an integral role in pharmaceutical research when developing drugs for human use. It is therefore imperative that animal models accurately represent human systems. In an attempt to reduce variability of test results, animals are often kept in barren, non-natural conditions. There is, however, a growing awareness that environmental enrichment will increase the validity of test results. The aim of the present study was to allow animals to control their environment using operant conditioning procedures, and to assess the effect of control on cognitive tasks. Four predictions were tested: 1. Rats (Rattus norvegicus) will control three stimuli (light, sound and a running wheel). 2. Animals will exhibit preferences for particular stimulus strengths. 3. Animals that exert control over the environmental stimuli will show increased performance in cognitive tasks compared to animals that lack control.4. Animals that can control environmental stimuli will have lower corticosterone levels than animals that lack such control, where corticosterone levels are used as an assessment of stress. Experimental subjects in both experiments did show control over a light stimulus, and performed significantly better in a discrimination task as compared with subjects that could not control their environment. There was no difference in corticosterone levels between control and experimental subjects. These results will contribute to an understanding how enrichment and control of environmental stimuli, in particular, affect the welfare of animals in captive environments, and aid in designing experimental conditions that will produce animal models that will increase validity and reliability in research.

  • FORMATIVE ASSESSMENT THROUGH WRITTEN FEEDBACK: EXAMINING ELEMENTARY SCHOOL TEACHERS' WRITTEN FEEDBACK BELIEFS AND PRACTICES, AND THE EFFECT OF MODELS ON WRITTEN FEEDBACK

    Author:
    Caterina Almendral
    Year of Dissertation:
    2014
    Program:
    Educational Psychology
    Advisor:
    Helen Johnson
    Abstract:

    The current study explored three main aspects relating to the use of written feedback as a formative assessment tool: the types (form or content) of written feedback provided by elementary school teachers and the levels (task, process-Self-Regulation) at which those types of feedback are provided; whether elementary school teacher beliefs about written feedback principles and their own written feedback practice correspond to the actual written feedback they provide; and whether exposure to a model of written feedback influences teacher written feedback practice. Data were collected from 188 elementary school teachers spirally assigned to five groups (four treatment, one control). Treatment groups were exposed to different written feedback models and subsequently all teachers were asked to provide written feedback on a fifth grade student's social studies writing sample. All teachers responded to a demographic survey as well as a questionnaire containing a series of questions related to their beliefs about written feedback and their written feedback practice. Findings showed that elementary school teachers provided form type comments almost ten times more frequently than content type comments. Teachers' beliefs regarding feedback practices did not match the actual feedback provided on the Written Task. Specifically, teachers believed that they provide content written feedback more frequently than was reflected in their actual feedback. There was no statistically significant relationship between teacher beliefs about process-SR related feedback principles and the actual number of process-SR level comments teachers gave on the Written Task. Exposure to written feedback models influenced the levels of written feedback participants delivered. Group 1 (form and task) provided significantly more task level feedback than Group 2 (form and process-SR) or the control group. Further, trend level differences were found between Group 2 and Group 1, with Group 2 providing more process-SR comments than Group 1. No differences were found by written feedback type or between Group 3 (content and task) and Group 4 (content and process-SR). Study findings suggest that teachers would benefit from support geared towards enhancing their written feedback practice to provide more content comments at the process-SR level. Practical and classroom applications are discussed.

  • Effects of Phonological Neighborhood Density on Lexical Access in Adults and Children with and without Specific Language Impairment

    Author:
    Diana Almodovar
    Year of Dissertation:
    2014
    Program:
    Speech & Hearing Sciences
    Advisor:
    Richard Schwartz
    Abstract:

    The present study was designed to examine how adults, children with typical language development (TLD), and children with Specific Language Impairment (SLI) process words from sparse and dense phonological neighborhoods, using the Cross Modal Picture-Word Interference Paradigm. The participants were asked to label a picture presented on a computer screen, while ignoring auditory distractors (interfering words or IWs) presented over headphones. The target items were manipulated according to neighborhood density (high and low density words), and the auditory distractors were either identical to the target, a neutral distractor (good), phonologically related (by rhyme), or unrelated to the target item. The interfering words were presented either before the target item ( -750, -450, or -150 ms ) before the picture, or after the picture ( +150 ms ). Participants were asked to name the pictures as quickly as possible, while ignoring the auditory distractors. Reaction times and error rates were measured. Eleven children with SLI (6;5-10;1), ten children with typical language development (6;10-10;2), and 22 young adults participated in the study. The results revealed that adults demonstrated increased sensitivity to rhyme-related distractors in the Low Density condition only, reflecting less detailed phonological representations of low density words. Children with TLD and SLI both demonstrated less interference of related IWs in both the high and low density conditions. There were no significant group differences in reaction time or overall error rates. However, the SLI group produced significantly more errors on low density words than the TLD group. In addition, children with SLI demonstrated similar response time differences for the related and unrelated items for both density types, while the children with TLD appeared to benefit more from the related distractors in the low density condition. The results are discussed in relation to the Lexical Restructuring Model (Metsala & Walley, 1998).

  • The Vocal Behaviors of Captive North American River Otters (Lontra canadensis) Individual differences and shared repertoires

    Author:
    Carla Almonte
    Year of Dissertation:
    2011
    Program:
    Biology
    Advisor:
    Richard Veit
    Abstract:

    The current information on the vocal repertoire of the North American River Otter is very limited. To date there have been no direct studies conducted on their repertories. In this study, I examined the vocal behavior of 12 captive river otters. The discriminant function analysis suggests that river otters have 4 distinct call types with 7 sub-call types and one call the whistle is unique to one group of pups. The results of the Kruskal-Wallis comparing acoustical structures shows strong evidence for the presence of individuality with some individuals showing greater differences in comparison to the others. I also examined the differences in sexes and age groups, and the results show that unique calls are present, and there are significant differences across groups when comparing acoustical structures. Finally, I examined the uses of vocalizations, and the results show a positive correlation between the duration, max frequency, and max power of the call and the arousal state of the individual producing the call. Specific call types also showed tendencies to be produced when the individual was in a particular interaction (asocial or social) and when in a particular arousal state.

  • ROUTING PROTOCOLS ENHANCEMENT FOR DELAY TOLERANT NETWORKS

    Author:
    Fuad Alnajjar
    Year of Dissertation:
    2010
    Program:
    Engineering
    Advisor:
    Tarek Saadawi
    Abstract:

    Routing in Delay/Disruption Tolerant Networks (DTN) is active area of research and acquires the attention of researchers as being the most adequate solution for the problem of intermittently connection in Mobile Ad hoc Networks (MANET). The challenge is to find a routing algorithm that can deal with dynamic environment causing networks to split and merge, considering nodes mobility. In this dissertation we enhance the performance of DTN routing protocols in Delay Tolerant Mobile Ad Hoc Networks by accomplishing the following goals to address the routing challenges: * Design a new probabilistic routing protocol based on history of encountered nodes. * Determination of strength and weakness of DTN routing protocols by comparison. * Enhancing DTN routing protocols by inclusion of study of the impact of link availability on performance of the DTN-based protocols * A Cross Layer Design (CLD) to enhance service quality of some common MANET-based routing protocols. v We have designed a DTN-based probabilistic routing algorithm using the concept of History of Encounters, HEPRA. Our routing protocol relies on the knowledge of the mobility of nodes and uses the history of encountered nodes to predict its future suitability to deliver messages to next node toward destination. The probabilistic routing approach is built on a store-carry-forward network to deliver messages to final destination in MANET environment. We evaluate the performance of HEPRA in various network environment behaviors. We present an evaluation and analysis of performances of some common DTN routing protocols including HEPRA in terms of different parameters in MANET environment. We illustrate the behaviors of the DTN routing protocols in terms of various parameters and variables. This evaluation presents the strengths and weakness of selected protocols. We study the impact of link availability as a parameter of the physical layer environment on the performance of DTN routing protocols. This study is the first research analysis of the impact of physical layer parameters on the performance of DTN routing protocols. We demonstrate through the simulation how those protocols act against changes in network environment. We propose a CLD to attain a reliable data transmission in MANET. We present a model that allows the network layer to adjust its routing protocol dynamically based on Signal Noise Ratio (SNR) and Received Power (RP) along the end-to-end routing path for each transmission link to improve the end-to-end routing performance in MANET environment. In this dissertation, we present the design basis for those contributions, illustrate and evaluate our design efforts, and discuss the advantages of our models.

  • Hispanic Catholic Women Converting to Islam/Latinas Converting to Islam in New York

    Author:
    Amalia Alonzo
    Year of Dissertation:
    2014
    Program:
    Middle Eastern Studies
    Advisor:
    Bryan Turner
    Abstract:

    This paper explores the topic of religious conversion in relation to Pierre Bourdieu's theory of habitus, with a focus on Catholic Latina converts to Sunni Islam. Bourdieu suggests that these types of religious choices are not choices at all, but predetermined by an individual's history, culture, and setting. That is, an individual already has dispositions that are taken for granted. While this study's participants report that Islam is a new religion for them and not a continuation of their Catholic faith (as habitus would suggest,) this study shows that these converts retain dispositions that are consistent with their previous religious identity. However, there are limits to the theory of habitus when analyzing complex, patterns of behavior including religious conversion. Therefore, a theory of reflexive-identity formation is also considered. I argue that these Latina converts are breaking down traditional religious boundaries and, in doing so, they embody the complexity of a modern identity.

  • Molecular Dynamics of Shock Wave Interaction with Nanoscale Structured Materials

    Author:
    Ahmad AL-QANANWAH
    Year of Dissertation:
    2012
    Program:
    Engineering
    Advisor:
    Yiannis Andreopoulos
    Abstract:

    Typical theoretical treatments of shock wave interactions are based on a continuum approach, which cannot resolve the spatial variations in solids with nano-scale porous structure. Nano-structured materials have the potential to attenuate the strength of traveling shock waves because of their high surface-to-volume ratio. To investigate such interactions we have developed a molecular dynamics simulation model, based on Short Range Attractive interactions. A piston, modeled as a uni-directional repulsive force field translating at a prescribed velocity, impinges on a region of gas which is compressed to form a shock, which in turn is driven against an atomistic solid wall. Periodic boundary conditions are used in the directions orthogonal to the piston motion, and we have considered solids based on either embedded atom potentials (target structure) or tethered potential (rigid piston, holding wall). Velocity, temperature and stress fields are computed locally in both gas and solid regions, and displacements within the solid are interpreted in terms of its elastic constants. In this work we present results of the elastic behavior of solid structures subjected to shock wave impact and analysis of energy transport and absorption in porous materials. The results indicated that the presence of nano-porous material layers in front of a target wall reduced the stress magnitude detected inside and the energy deposited there by about 30 percent while, at the same time, its loading rate was decreased substantially

  • Making Conversation: The Poetics of Voice in Modernist Fiction

    Author:
    Elizabeth Alsop
    Year of Dissertation:
    2012
    Program:
    Comparative Literature
    Advisor:
    John Brenkman
    Abstract:

    This dissertation examines the function of dialogue within modernist fiction, and argues that it can be seen to assume a substantially expanded and diversified role in early twentieth-century narrative texts. While existing accounts of fictional speech stress its capacity to develop character or advance plot, I contend that modernist authors began using speech differently than it had historically been used in the novel: less for characterizing and plot-advancing purposes, than for rhetorical and poetic ones. My primary case studies include a cross-section of British and American modernist texts - including Henry James's The Ambassadors, Ernest Hemingway's The Sun Also Rises, James Joyce's "The Dead," Virginia Woolf's The Waves, and William Faulkner's The Sound and the Fury and Absalom, Absalom! - as well as examples from post-War Italian narrative, which reflect the influence of Anglophone modernism. Through close, comparative analyses of how fictional voice is deployed in these texts, and by drawing on a range of literary and narrative theory (by Mikhail Bakhtin, Franco Moretti, and Sharon Cameron among others) I demonstrate that these writers frequently "make" conversation less to express character, than to communicate ideas or affects that exceed character. In particular, I disclose the tendency for discourse within these fictional environments to belong to more than one speaker - or conversely, to none. By challenging the attributive logic used to make sense of represented speech, these texts encourage us to refocus our critical attention away from discrete utterances, and toward the larger system of utterances that emerges in a given work. In this way, I argue, modernist fiction seems to demand (and reward) a new mode of reading and interpreting fictional dialogue: one which takes into account how characters say, as well as what they say, and which treats dialogue's form as at least as rich a source of meaning as its content.

  • FACIAL EMOTIONAL EXPRESSION FOLLOWING VOICE TREATMENTS IN INDIVIDUALS WITH PARKINSON'S DISEASE

    Author:
    Karin Alterescu
    Year of Dissertation:
    2012
    Program:
    Psychology
    Advisor:
    Joan Borod
    Abstract:

    A growing body of work has documented impairments in emotional facial expression (i.e., masked facies) in individuals with Parkinson's disease (PD). These impairments negatively impact patients' social interactions and functioning in daily life. However, little attention has been given to remediating facial emotional expression deficits in PD. Preliminary research has demonstrated that the treatment of voice using the Lee Silverman Voice Treatment (LSVT®; Ramig et al., 1995) has beneficial effects on limited aspects of facial expression in PD (Spielman et al., 2003). The present study extends the literature by examining the effects of two voice treatments on facial expression in PD in a comprehensive way, including facial mobility (FM) and three aspects of facial emotional expressivity (i.e., frequency [EF], variability [EV] and intensity [EI]). Participants included 56 posers, individuals who produced emotional and non-emotional monologues, and 18 raters, individuals who rated posers' facial expressions from video-recorded monologues. Ratings were made on a 7-point Likert scale for the four aspects of facial expression. Raters were trained to criterion, and reliability was high for each emotional expression variable (Intraclass Correlation Coefficient range .85 to .90). The study included four poser groups: 3 PD groups whose posers were randomly assigned into an LSVT, Articulation Voice Treatment (ARTIC), or a no treatment control group, and a demographically matched healthy control group (NC). Findings revealed that PD male posers displayed impaired facial expression at baseline compared to NCs on all variables examined, although PD women did not differ from NCs for any aspect of facial expression. Treatment findings showed that patients who received LSVT were rated as having higher FM, EF, EV, and EI after treatment, four weeks later, than at baseline. This increase was not observed for the 3 other poser groups. It is speculated that LSVT improves facial expression because facial and vocal expression are emotional communication channels that exist within a larger network of emotional processing. Facial and vocal emotional expression are linked at several levels of neural organization: cortical, subcortical, and cranial nerve. The broader clinical implications of our findings are that masked facies can be remediated using LSVT.

  • Synthesis of Biologically Important C-glycosides from Simple C-glycosyl Alkenes

    Author:
    Ahmad Altiti
    Year of Dissertation:
    2014
    Program:
    Chemistry
    Advisor:
    David Mootoo
    Abstract:

    Abstract Synthesis of Biologically Important C-glycosides from Simple C-glycosyl Alkenes by Ahmad Altiti Adviser: Professor David Mootoo C-Glycosides are carbohydrate analogues in which the glycosidic oxygen is replaced with a methylene substituent. Because of their stability under acidic hydrolysis or enzymatic cleavage, they are widely used as mimetics of their parent O-glycosides in medicinal chemistry. This thesis describes the development of new synthetic methods for C-glycosides, which center on the use of readily available, simple C-allyl glycosides as precursors. C- glycosides of three structurally distinct and pharmacologically interesting carbohydrates, the immunostimulatory glycolipid C-KRN700, the insulin mimetic glycoinositol β-galactosamine-(1→4)-3-O-methyl-D-chiro-inositiol (INS-2), and α-mannose-(1→6)-D-myo-inositiol, a subunit of the cell wall in Mycobacterium tuberculosis, will be used as test cases for these methodologies. Chapter I and II α-Galactosylceramide (α-GalCer) also called KRN7000 is a potent stimulant of invariant natural killer T (iNKT) cells. The C-glycoside of KRN7000 shows higher activity than its parent O-glycoside against malaria and melanoma in mice models. The high activity of C-KRN7000 could be due to its hydrolytic stability or the way in which it interacts with receptors in the immunological pathway. New analogues of C-KRN7000 are needed to elucidate this picture. Two robust synthetic methodologies that can provide structurally diverse structures in the polar head region were developed. Chapter 1 describes the first approach, which entails: (i) the convergent union of relatively simple and readily accessible carbohydrate and lipid precursors to give a homoallylic alcohol, (ii) introduction of the amino group in the target via an iodocyclization reaction on derived homoallylic trichloroacetimidates and carboimidothioates. The cyclization reactions were evaluated for both E and Z alkene substrates. The E and Z trichloroacetimidates showed opposite facial selectivities, with the Z isomer providing the desired result for C-KRN7000. This stereochemical result is as expected for related electrophilic cyclizations. In contrast both E and Z carboimidothioates showed the same facial selectivity, in favor of the desired product. The iodo-carbamate products that were obtained from the reactions of the E and Z carboimidothioates were both processed to C-KRN7000 via established and straightforward deiodination and alcohol protecting group procedures. However, the elaboration of the iodo-oxazine products from the tricholoroacetimidate reactions was problematic. Chapter II describes the second method, which centers on the Lewis acid mediated crotylation reaction of a C-glycoside crotylstannane on a simple α-alkoxy aldehyde to give diastereomeric homoallylic products. These products can be transformed to different diastereomers of C-KRN7000, and homologated and reverse amide analogues thereof. The diasteroselectivity of the crotylation reaction was examined and found to vary with the Lewis acid or the protecting group on the aldehyde. The key step in the processing of the crotylation products to C-glycosides of C-KRN700 was a Curtius rearrangement on the acyl azide derived from the terminal alkene in the crotylation product. This chemistry was applied to C-KRN7000, its amide epimer, and an analogue of C-KRN7000 with a fluorine atom at the pseudoanomeric position. Chapter III As an extension to the crotylation chemistry in Chapter II, we developed a new approach to the synthesis of C-glycoinositols, which pivots on late stage construction of the inositol ring. The strategy uses easily accessed 3,4-dialkoxy-4-enals as aldehyde partners for C-linked crotyltins. A ring closing metathesis (RCM) on the crotylation product gives a C-linked dioxygenated cyclohexene that can be converted to a fully oxygenated C-glycoinositol by a dihydroxylation reaction. Different alkene functionalization reactions on the RCM product leads to inositol with different functional groups. Using different combinations of crotylstannane and aldehydes can further increase analogue diversity. For a given crotylstannane the diastereoselectivity of crotylation reaction was found to vary with choice of Lewis acid and the stereochemistry of the aldehyde partner. This methodology was applied to the C-glycosides of INS-2 and α-mannose-(1→6)-D-myo-inositiol. The results in Chapters II and II illustrate the attributes of the C-glycoside crotyltin methodology: (i) easy availability of the crotyltin and aldehyde precursors; (ii) the compatibility of the key segment coupling reaction with a variety of different functional groups; (iii) the synthetic versatility of the reaction products, which allows for a high throughput of complex and diverse glycomimetic libraries.